Psephoderma is a placochelyid placodontian reptile from the Late Triassic of Italy. It was named in 1858 by Christian Erich Hermann von Meyer. It was one of the last placodonts to live, as well as one of the largest.
Physiology[]
Like its close cousin, Placochelys, Psephoderma resembled a turtle, with a broad, shell-covered body, large flippers, a moderately long tail, and a small head with small jaws. However, it had a few differences; its shell was divided into two parts (one covering the thorax/upper body, and the other protecting the pelvis), and its flippers still had claws on them. Its body was covered in scaly skin, and mostly covered by its hard shell.
Diet[]
Psephoderma was a predator, preying on bivalves. Instead of having normally shaped jaws with chisel-like incisors on the front of them, it had a small beak used for picking bivalves off the seafloor; however, it still had flat back teeth designed for crushing them.
Ecology[]
So far, all we know about Psephoderma is that instead of having one big shell covering its body, it had a larger thoracic shell combined with a smaller pelvic shell, which gave it more agility than single-shelled placodonts like Henodus and Placochelys; as well as this, its flippers were not fully developed and still had claws on them (allowing it to spend a reasonable amount of time on land), and it had a small, turtle-like beak used for picking up shellfish from the seafloor before passing them into its mouth before crushing them with its flat back teeth (in a similar manner to Placochelys).